Crankshaft grinder



1936- G. H. GOULDEN I CRANKSHAFT GRINDER Filed July 16, 1935 INVENTUR Q4/4017) ATR )RNEY.

. 20 A further object of the invention is t6 so con- A grinding shaft 23 extends longitudinally ing and throughout the description. motor (not shown).

40 .-tion, illustratingthe interior construction. ground and the 'device is assembled as shown in 45 In the specification the cylindrical bearing surthe'bearing surface. The crank shaft Iliais now Patented Nov. 24, 1936 UNITED, STATES PATENT OFFICE 2,061,264 CRANKSHAFT GRINDER George H.- Goulden, Denver, Colo. Application July is, 1935, Serial No. 31,555

8 Claims. 01. 51-241) This invention relates to a device for grinding to have'bearing surfaces 30 and iii, formed of the bearing surfacesv of automotive engine crank hardened steel blocks, inset into the shaft reshafts. It is an exceedingly'dimcult and expen- 'ceiving notchesforrned in the housing blockl3 'sive procedure to remove the crank shaft from and the head block M so that they will withstand 5 an engine in order to regrind or true up the bearwear and will be renewable. The clamp screws 5 ing surfaces thereof. V I5 are threaded into a cross bar l6 which is sepa- The principal object of this invention is to' rated from the head block I4 by means of a leaf provide a device which can be attached to the spring ll. various bearings of a crank shaft without-remov- A shaft sleeve l8 passes longitudinally through 10 ing the latter from the engine and which will the housing block l3, and-is supported therein 10 accurately and rapidly true up the bearing surupon an adjusting nut l9 threaded upon feed faces'thereof. v threads upon the sleeve. The nut i9 is posi- Another object of the invention is to provide a tioned in a lateral slot extending through the deviceiof this character which can be accurately block l3. A spring washer 35 is preferably placed 15 and minutely adjusted to remove any desired above the feed nut I9 to hold it against the bot- 15 amount from the bearing surface to produce an tom of its slot so as to remove any'lost motion accurate new surface upon the bearing-and which in adjustment thereof. A pin 2| projects from will be adaptable to crank shafts of different the block l3 into a guide slot or keyway 22 in the diameters and widths. sleeve to prevent rotation of the latter.

struct the device that it can be regulated to through the sleeve l8 and'is supported therein grind more upon one extremity .of the bearing between an upper thrust bearing 24 and a lower surfaces than upon the other extremity, if dethrust bearing 25. Clamping nuts26 clamp the sired, so as to accurately align [a badly worn or thrust bearings to the end of the sleeve 18. The tapered bearing. upper extremity of the shaft 23 terminates in a 2 Other objects and advantages reside inthe grinding head 21 to which a suitable grinding detailed construction of the invention, which is wheel 28 is attached by means of an attachment designed for simplicity, economy, and efficiency, screw 29. If-desired, a handle member 32 may These will'become more apparent from the folbe placed around the shaft sleeve l8. lowing description. H The housing l3 carries two bearing surfaces 30 In the following detailed description of the positioned at from the vertical, and the head invention reference is hadto the accompanying block l4 carries two similar surfaces 3|. The drawing which forms a part hereof. Like nushaft 23 may be driven in any desired manner merals refer to like parts in all views of the drawsuch as from a flexible drive shaft or a portable In the drawing:-- 1 In use, the bottom of the crank case is removed Fig. '1 illustrates the invention applied to a from the automotive engine and the connecting typical crank fshaft. rods are disconnected from the crank shaft. The Fig. 2 is aside elevation thereof, partly in sechead block 14 is placed over the bearing to be Fig. 3 is a horizontal cross section, taken on Fig. 1. The shaft 23 is rapidly rotated at ap-' the line 33,'Fl g. 2/ proximately 3,000 R. P. M. The feed nut I9 is Fig. 4' is a similar-section taken on the line turned to thread'the sleeve l8 upwardly until 4 -.4, Fig. 2. j I the face of the grinding wheel 28 contacts with faces upon the-crank shaft which rest inthe rotated, allowing thegrinding tool to depend main crank case bearings and the connecting rod therefrom, and the sleeve is fedv upwardly by bearings will be designated simply as bearings. means of the nut l9 until the hearing has been In the drawing, a typical crank shaftis ,indiground to the desired true diameter.

,cated at l0 withit's main bearings at H and its In placing the device on th bearing, the bolts connecting rod-bearings at l2; The invention l5.are drawn sufficiently tight to slightly comcomprisesa main housing block l3 to which a press the leaf spring IT. This allows the bearing head block I4 is held by-means of suitable clamp to rotate between the blocks l3 and II against screws IS. The blocks l3 and H are notched to the bearing surfaces 3i! and 3|. The latter sur- 66 receive'the crank shaft bearings. It ispreferred faces hold the grinding shaft accurately at right angles to the bearing surface so as to maintain the faceof the grinding wheel flat against the surface. As the diameter of the bearing is reduced by grinding, the spring II will gradually expand to take up the loss and maintain the contacts at 30 and 3|.

The device is designed to grind the full width of the bearing at once, and the grinding wheels 28 are furnished in diameters equal to the full width of various bearings. The head blocks I are also furnished in thicknesses equal to the full width of the various bearings so as to accurately hold the grinding wheels centered on bearings of given sizes. The housing block I3 is of a width to fit into the smallest expected bearing.

It is desired to call attention to the fact that the bearing surfaces 30 and 3| are offset to one side of the center line of the grinding shaft 23. This positions the line of contact with the bearing to one side of the center of the grinding wheel. as indicated by the vertical center lines in Fig. 3, so that the shaft is ground throughout the entire length of the line of contact without interference by the position of the attachment screw 29.

A tapped hole 33 may be formed .through the head block in alignment with a hole 34 in the head block l6 so that a tube may be threaded into the head block for supplying water or grinding fluid to the shaft if desired. ordinarily however, this is not necessary.

For accurate feeding purposes, it is preferred to cut the threads 20 forty threads per inch and to divide the surface of the feed nut l9 into twenty five division notches with a click spring 36 snapping into the division notches. This assures the operator that each click will feed the grinding wheel 28 one one-thousandth of an inch toward the work.

Occasionally a worn bearing will be encountered which has become badly tapered, that is, it is of much smaller diameter at one end than at the other. If the two blocks l3 and M are clamped against such a hearing it might result in an inaccurate or tapered grinding. To meet such conditions two relatively long set screws 31 are threaded longitudinally through the housing block l3 at diagonal corners thereof. By threading one of these screws against the head block at the smaller end of a tapered hearing it will prevent the two blocks from being pulled together on the taper of the bearing and will favor the grinding of the larger end of the bearing.

While a specific form of the improvement has been described and illustrated herein, it is desired to be understood that the same may be varied, within the scope of the appended claims, without departing from the spirit of the invention.

Having thus described the invention, what is claimed and desired secured by Letters Patent is:--

1. A crank shaft grinding tool comprising: a housing block provided with a V-shaped notch for receiving a crank shaft bearing; a longitudinally movable sleeve extending from the bottom of said notch through said block; a grinding shaft" nally movable sleeve extending from the bottom of said notch through said block; a grinding shaft supported in said sleeve; a grinding wheel mounted on said grinding shaft in said notch; means for clamping said bearing in said notch; threads formed upon said sleeve; and a nut held in said housing block in mesh with said threads to feed said sleeve toward said bearing the edges of said nut projecting through the sides of said block.

3. A crank shaft grinding tool comprising: a housing block provided with a notch for receiving a crank shaft bearing; a longitudinally movable sleeve extending from said notch through said block; a grinding shaft supported in said sleeve; a grinding wheel mounted on said grinding shaft in said notch; means for feeding said sleeve toward said bearing; a. notched head block for holding said bearing against said housing block; clamping bolts extending between said head and housing blocks; a nut member threaded on said clamping bolts; and a spring interposed between said nut member and said head block so as to resiliently clamp said' blocks against said bearing.

4. A crank shaft grinding tool comprising: a housing block provided with a V-shaped notch for receiving a crank shaft bearing; a longitudinally movable sleeve extending from the bottom of said notch through the opposite face of said block; a grinding shaft supported in said sleeve;

'a grinding wheel mounted on said grinding shaft in said notch; means for clamping said bearing in said notch; and means for feeding said sleeve ing shaft in said notch; means for feeding said sleeve toward said bearing; a notched head block forholding said bearing against said housing block; means for drawing said head block toward said housing *block; and set screws carried by said housing blockfor contacting said head block at either side so as to prevent the drawing together of said blocks at either desired side.

6. A crank shaft grinding tool comprising: a housing block provided with a notch'for receiving a crank shaft bearing; a longitudinally movable sleeve extending from said notch through said block; a grinding shaft supported in said sleeve; a grinding wheel mounted on said grinding shaft in said notch; means for clamping said a bearing in said notch; threads formed upon said 7 sleeve; a nut held in said housing block in mesh with said threads to feed said sleeve toward said bearing said nut projecting beyond the sides of said block; and means for preventing rotation of said sleeve in said housing block.

7. A crank shaft grinding tool comprising: a housing block provided with a notch for receiving a crank shaft bearing; a longitudinally movable sleeve extending from said notch through said block; a grinding shaft supported in said sleeve; a grinding wheel mounted on said grinding shaft in said notch; means for feeding said sleeve towardv said bearing; a notched head block for holding said bearing against said housing block, said head block being longitudinally grooved; a

cross bar mounted in said groove; 8. spring inter- V posed between said cross bar and said head block; and a pair of clamp screws extending from said housing block through said head block and threaded into said cross bar so as to clamp said blocks together against abearing' while compressing said spring.

8. A toolfor grinding crank shaft bearing surfaces comprising a relatively flat, elongated, rectangular block having a thickness substantially equal to the width of a crank shaft bearing onpositely inclined surfaces extending transversely across the inner extremity of said block so as to form a V-shaped notch therein for receiving a crank-shaft bearing surfacathere being a counter-bore extending longitudinally into said block from the bottom of said notch and a shaft bore extending longitudinally through said block from the bottom of said counter-bore; a bearing sleeve extending from said counter-bore through said shaft bore and projecting from the outer extremity of said block; a thrust bearing on the inner extremity of said shaft within said counterbore; a grinding wheel in said counterbore; a drive shaft extending from said wheel through said thrust bearing and through said sleeve and projecting beyond the outer extremity thereof; threads formed on said shaft within said block, there being a slot formed completely through said block opposite said threads; a relatively flat nut positioned in said slot and threaded upon said sleeve, said slot acting to prevent longitudinal movement of said nut; means for preventing rotation of said sleeve in said block; and means for clamping the inclined surfaces of said V- shaped notch against a bearing surface of a crank shaft.

GEORGE H. GOULDEN. 

